Surface assembly of pyridyl-substituted porphyrins on Au(111)investigated in situ using scanning probe lithography

摘要

Scanning probe characterizations of porphyrin patterns created by nanografting were used to provide insight for the molecular orientation and surface assembly of porphyrins with pyridyl and phenyl substituents. In-situ AFM provides highly local views of the assembly of pyridyl-substituted porphyrins on surfaces of Au(111). Matrix self-assembled monolayers(SAMs) of n-alkanethiols furnish a molecular ruler for calibrating height measurements. Nanografting can be used for local measurements of the thickness of porphyrin films in situ by comparison with heights of n-alkanethiol nanopatterns. When nanografted, pyridyl porphyrins were found to assemble onto gold directly into an upright configuration, and surface binding is likely mediated through nitrogen-gold chemisorption.